Add PangoMatrix type for affine transforms.

Fri May 28 11:39:39 2004  Owen Taylor  <otaylor@redhat.com>

        * pango/pango-types.h pango/pango-utils.c: Add PangoMatrix
        type for affine transforms.

        * configure.in pango.pc.in pango/Makefile.am: Add a -lm
        dependency for PangoMatrix operations.

        * pango/pango-context.[ch]: Add pango_context_set/get_matrix().

        * pango/pangoft2-render.c pango/pangoft2-private.h: Add
        code for drawing antialiased transformed rectangles and
        squiggly error underlines.

        * pango/pangoft2.[ch]: Add pango_ft2_render_transformed(),
        pango_ft2_render_layout_subpixel(),
        pango_ft2_render_layout_line_subpixel(), implement transformed
        rendering.

        * pango/pangofc-font.c: Pass any transformation matrix on to
        fontconfig when creating the pattern for a PangoFcFont.

1 files changed, 57 insertions, 0 deletions

diff --git a/pango/pango-types.h b/pango/pango-types.h
index 6f515ead..55283fbd 100644
--- a/pango/pango-types.h
+++ b/pango/pango-types.h
@@ -33,6 +33,8 @@ typedef struct _PangoEngineLang PangoEngineLang;
 typedef struct _PangoEngineShape PangoEngineShape;
 
 typedef struct _PangoFont PangoFont;
+
+typedef struct _PangoMatrix    PangoMatrix;
 typedef struct _PangoRectangle PangoRectangle;
 
 /* Dummy typedef - internally it's a 'const char *' */
@@ -53,6 +55,61 @@ struct _PangoRectangle
   int height;
 };
 
+/**
+ * PangoMatrix:
+ * @xx: 1st component of the transformation matrix
+ * @xy: 2nd component of the transformation matrix
+ * @yx: 3rd component of the transformation matrix
+ * @yy: 4th component of the transformation matrix
+ * @x0: x translation
+ * @y0: y translation
+ *
+ * A structure specifying a transformation between user-space
+ * coordinates and device coordinates. The transformation
+ * is given by
+ *
+ * <programlisting>
+ * x_device = x_user * matrix->xx + y_user * matrix->xy + matrix->x0;
+ * y_device = x_user * matrix->yx + y_user * matrix->yy + matrix->y0;
+ * </programlisting>
+ **/
+struct _PangoMatrix
+{
+  double xx;
+  double xy;
+  double yx;
+  double yy;
+  double x0;
+  double y0;
+};
+
+/**
+ * PANGO_MATRIX_INIT
+ *
+ * Constant that can be used to initialize a PangoMatrix to
+ * the identity transform.
+ *
+ * <informalexample><programlisting>
+ * PangoMatrix matrix = PANGO_MATRIX_INIT;
+ * pango_matrix_rotate (&amp;matrix, 45.);
+ * </programlisting></informalexample>
+ **/
+#define PANGO_MATRIX_INIT { 1., 0., 0., 1., 0., 0. };
+
+PangoMatrix *pango_matrix_copy   (PangoMatrix *matrix);
+void         pango_matrix_free   (PangoMatrix *matrix);
+
+void pango_matrix_translate (PangoMatrix *matrix,
+			     double       tx,
+			     double       ty);
+void pango_matrix_scale     (PangoMatrix *matrix,
+			     double       scale_x,
+			     double       scale_y);
+void pango_matrix_rotate    (PangoMatrix *matrix,
+			     double       degrees);
+void pango_matrix_concat    (PangoMatrix *matrix,
+			     PangoMatrix *new);
+
 #define PANGO_SCALE 1024
 #define PANGO_PIXELS(d) (((d) >= 0) ?                             \
                          ((d) + PANGO_SCALE / 2) / PANGO_SCALE :  \